Method and apparatus for back facing



April 20 ,1926. 1,581,542:

F. J. PETERS METHOD AND AFPARATU S FOR BACK FACING Filed Jan. 20. 1925 zsneets-sheet 1 gwuentoz A ril20,1926. 1,581,542

F. J. PETERS METHOD AND APPARATUS, FOR BACK FACING Filed Jan. 20, 1925 2 Sheets-Sheet 2 k 29 17 f \l .2, so Z7 Patented Apr. 20, 1926.

UNITED "STATES 4 1,581,542 PATENT OFFICE.

FBEBEB'I PETERS, OF RICHMOND, INDIANA, ASSIGNOB TO THE NATIONAL AUTO- MATIC TOOL COMPANY, OF RICHMOND, INDIANA, A CORPORATION .OF INDIANA.

mn'rnon AND arrana'rns'ron BACK Enema.

Application filed January 20, 1925. Serial No. 3,680.

To all whom it may concern:

Be it known that I, FREBERT J. Pn'rans, a citizen of the UnitedStates, and residing at Richmond, in the county of Wayne and State of Indiana, have invented a new and Improved Method and Apparatus for Back Facing, of which the following specification is a full disclosure.

These inventions are concerned with the accomplishment of tooling-operations on certain local areas which, by reason of the shape of the work, are not approachable in a satisfactory manner by tools driven or mounted according to convention.

lln undertaking to overcome this difiiculty, it is now roposed to differentiate between the mounting ofthe cutter itself and the mounting of the shank which drii'es the cutter. are proposed, i. e., one providing a firm bearing for the cutter isolated from its driver, and the other making provision for independently journaling the driver; these two independent supports being so arranged with regard to the contour of the castlng that they will neitherinterfere with the casting nor will the casting interfere with the projecticn of the driver from its retracted position into its propelling engagement with the cutter. By this arrangement, the shaft for driving the cutter may be as long as desired and need be only of sufficient diameter to carry the torsional strains of rotating the cutter; the shaft not being obliged either to carry the working-load of thecutter or to contribute to the rigidity of the mounting of the cutter. Likewise, the cutter itself may be very accurately journaled in a mounting sutliciently rigid to ensure a smooth cutting action with asmuch precision as may be demanded. By appropriately constructing and independently mounting the small cutter-driving unit,-the driving shaft may be mounted in angular relationwith the axis of the cutter itself, and that shaft may be as long and as extensible as desired, so that internal areas of certain types of castings may be machined expeditiously. It is proposed, in applyingthe aforesaid features 0 con struction and steps of operation, to arrange for a relative movement between the work-- support and the support for the cutter to establish and maintain the cutting action until the tooling operation'has been completed.

The cardinal characteristics of this nevv lhat is to say, two distinct supports method and apparatus for machining areas not readily accessible, may be explained by which provides a hole for the bolt. Access to that region, is not infrequently obstructed by the general form of the casting and the method now in vogue'is irksome and occasions much loss of time; all of which is obviated by the herein proposed method and apparatus.

Other objects and advantages will be in part indicated in the following description and in part rendered apparent therefrom in connection with the annexed drawings.

To enable others skilled in the art so fully to apprehend the underlying features hereof that they may embody the same in the various ways contemplated by this "invention, drawings depicting a preferred typical construction have been annexed as'a part of this disclosure and, in such drawings, like characters of reference denote corresponding parts throughout all the views, of which Fig. 1 shows an elevation of a well known type of machine-tool embodying this invention. Fig. 2 is a plan showing one mannerof arranging the independently mounted cutters with relation to a given casting.

Fig. 3 is an end elevation of the mechanism Referring to Fig. 1, A designates .generally a standard multiple spindle drilling machine which, being well known to those skilled in the art need not be described in detail; it suflicing to point out that this machine provides a despressible head B furnishing a mounting for a plurality of spindles 1, 2, etc. which through suitable gearing, are simultaneously driven by a main shaft This shaft is splined through a drive box D- so as to be malntained in motion during the rise or descent of the head B. By power derived from a drive box E through the feed shaft F. which is splined toa gear within the .incorgrated in the form of a fixture which may. appropriately bol-tedtd'the table K; it being material whether the organization admits of being dismantled or whether it is permanently built in the machine as will be well understood. i

' Referring to Fig. 3, a work-support 3 is arranged in depressible relation with a base 4; it being conveniently sustained by appro- 'priate expansible springs 5, 6, etc., andguided in parallelism by appropriate guides 7 and 8. Adjusting-nuts 9 and 10, or any other "suitable, means, are provided to regu-' late the amount of clearance between the work-su port 3 and the base 4; in other words, t e extent to which the work support 3 may be'depressed.

The work or the casting will, of course,

vary in shape and contour according to the 1 nature of the production but, by way of illus-' tration, there isindicated by 11, a typical casting which presents flanges 12 and 13, the under'surfaces of which require to be machined; in this instance, to provide annular seats circumscribing the bolt holes indicated by 14 and 15. By reason of the conformation of the body piece of work, it will be seen that those areas arenot directly accessible to any conventionally driven tools but, by the present system may be machined with complete 'facility. Uprising from one side of the base 4 is a member 17 which maybe regarded as a por-- tion of an arm which terminates in an extremity 18 exte nding into a proximity with one of the areas to be machined. In this arm extremity 18 is journaled an isolated tool or cutter 19, and, in this instance, this cutter istubular in shape and provides a splined bore 20'which, as will be explained, is adapted to receive a. shank whereby it is rotated. The arm will'be shaped with regard to the character of the casting soas toextend to whatever portion requires to be machined,

' and it is proposed to so mount the, arm as to facilitate the removal and replacement of successive castings.

Referring to Fig. 2, it will be seen that the arms 18 and 21 are pivoted at 22 and 23 with the object of providing sufficient lateral dis placement to avoid contact with the inturned edges 24 and 25 of the casting. Suitable de portion 16 of this tents 26'and 27 will reserve the position of the arms 18 and 21 a r the casting has been put in place and at the same time will permit those arms to swing aside while the casting is being withdrawn. lVhere there is no need of providing for lateral clearance, the arm may be free from such pivots as indicated by the arm 28.

It is desirable, however, whenever variations will occur in the castings, to provide vmeans for adjusting the proximity of the cutting edges to the surface to be machined.

In that event, suitable slides 29 may be provided for the respective arms and some such means as a screw 30 may be arranged to adjust the position of the slides 29 as will be understood.

In certain cases, it is desirable to resort to displaceable supports for the cutters so as to accommodate a removal and replacement of the casting or to admit the cutters to special parts of'the casting, and in that event, the cutter support will be correspondingly constructed, for example, Fig. 3 shows a supporting member 31 pivoted at 32 to the base 4 but here also an arm33 is slidably'mounted on the support 31 and carries a cutter 34;

the relation between the pivot 32 and the cutter 34 being such that the support 31 may be swung outwardly and away to remove the cutter without interference with the edge 35 of the casting. This furnishes a means for expeditiously putting in and taking out the work. The arm 31 may be held rigidly during the-actual tooling operation by some such abutment as that indicated by 36 and by means of some such clamping bolt as mdicated by 37.

Afterthe parts have been assembled as shown, it is merely necessary to bring down the head *B. Journaled in that head, and driven by power means through suitable gearing, are a number of stubs 38 and 39 which are seated in a conventional manner in spindles 1 and 2, and so aligned as to be in registry with the apertures 14 and 15 in the holes of the casting and with the bores v of the respective cutters. These stubs therefore may be projected in paths clear of the casting and into engagement with the respective cutters; the stubs being squared or otherwise shaped to enter mto a spline-like engagement with the cutters for the purpose of imparting rotat1on thereto. Means are alsoprovided for causing an approachment between the cutters and the work; a very simple way of accomplishlng this being to mount a wide base plunger 40 on the head so as to terminate somewhat short of the extremities of the stubs 38 and i 39. This plunger will come in contact with the upper portion of the casting and, as the head B continues down, it will depress the casting and, through it, depress the table 3, and bring the casting against the then-rotatingcut-ters and bring about the. machining of the areas. Byappropriately adjusting the clearance space 41 which determines the extent of retreat of the table 3, the depth of'the machining operation can be accurately controlled and the operation can be accomplished very expeditiously.

To ensure the engagement of the stubs with the cutters and to permit the head to descend positively without any possibility of obstruction, the stubs may be yieldably mounted to be impositively advanced; an

expansilespring 41 being arranged 'to urge some such shoulder as 42 of the stub 39 (non-rotatably translatable in the holder 43) against a suitable counter-part shoulder in the holder which, in this instance, is shown for rotating thecutters.

edge, readily adapt it for various utilizations by retaining one or more of the features that, from the standpoint of the prior art, fairly constitute essential characteristics of either the generic or specific aspects of this invention and, therefor, such adaptations should be. and are intended to be, comprehended within the meaning and range of equivalency of the following claims.

Having thus revealed this invention, 1

claim as new and desire to secure the fol lowing combinations and elements, or equivalents thereof, by Letters Patent of the United States: A

l. A method of back-facing work which consists in perforating said work then alignin the perforation coaxially with a non-yie dable but rotatable facing tool having an axial bore; then inserting throu h said perforation a stub into driving re a tion with the bore of said facing-tool to rotate it; and then bodily shifting the work against the facing-tool until it has completed its back-facin operation.

2. A backacing apparatus combining a depressible work-support; a non-depressible support for a facing-tool; a tubular facing tool journaled in the last named support; a

depressible head; a power-rotated stub mounted in said head in coaxial ali cut with said facing-tool and adapted du the descent of said head to enter the bore 0 said facing-tool in splined relation-therewith to rotate it; and means 0 rative after the es the work'to move into contact with said faclng-tool until the back-facing operation has been completed.

" 3. In aback-facing machine, two rela- Y tively shiftable supports; a tubular facingtool journaled in the one; a power-rotated stub yieldably journaled in the other in coaxial alignment with said facing-tool; a work-support for mounting work with its perforation in ali ment with said stub; and means for pr ucing relative approach ments between said supports first to engage tion and then to effect an engagement be-- tween the then-rotating facing-tool and the work to accomplish the back-facing operation.

4. A method for tooling an indirectly approachable region of work which consists in idly journalling a tool upon an arm contoured to hold said tool opposite to said region; then establishing a propelling engagement between said tool while stationary and a driver therefor; and then effecting a relative movement between said arm and said work to bring the tool journaled on said arm into tooling relation with said indirectly approachable region.

5. An apparatus for tooling an indirectly approachable region of work combining a work-support; an arm shaped to reach said region; an isolated tool journaled on said said region; a normally disconnected driver adapted to be bodily moved into propelling relation with said tool; and means for then efi'ecting are'l'ative movement between said arm and said work-support to engage said tool with said work and cause it to perform its tooling-operation on said region.

6. A back-facing apparatus combining a depressible work-support; a tool-support adapted to be shifted laterally from an idle position into an operative relation with the work; a tubular facing-tool jo'urnaled in said support; a head; a power-rotated stub mounted in said head in coaxial alignment withsaid facing-tool and adapted to be depressed to enter the bore of said facing-tool in splined engagement therewith; means operative after the establishment of said splined engagement to depress the worksupport and thereby cause the work bodily to move intocontact with said facing-tool until the back-facing operation has been completed.

7. In a' back-facing machine, two relatively approachable supports; a tubular facing-tool journaled in the one, said toolsupport being laterally laceable, a power rotated stubjournaleil i n the other in coaxial alignment with said facin -tool;

a work-sup rt for so mounting wor .that it will provide clearance for the path of said stub but will be in oppositionwith cutting portions of said tool; and means for prosaid facing-tool and stub in propelling relaarm and located thereby in opposition with I llll and

8 A method of machining an indirectly accessible area of work which consists in work.

rotatably supporting an isolatedtool in opposition with said area; then projecting a rotatable shaft along a path unobstructed by said work to establish a propelling relation'between said rotatable shaft and said independently supported tool; and then causing a relative approachment between the independently-supported tool and the work while litilizlng said shaft for the sole purpose of rotating said tool.

9. The combination of claim '5 in which the arm is adapted'to be initially moved from an tion.

10. The combination of claim 5 in which the arm is combined with means for adjusting the mounting of the tool to regulate the initial clearance between the tool and the region to be machined.

11. An apparatus for simultaneously ma chining several indirectly accessible areas of work, said apparatuscombining a; plurality of arms eachshaped independently to, terminate adjacent a respective area; a plurality of isolated cutters,each inde ndently journaled on the extremities 0 said arms respectively; a plurality of positively rotated driving shafts adapted to be projected along paths unobstructed by the work to establish propelling relations with the respective cutters; a work-support; and means for producing a irelativeapproachment between said work-support and said arms to cause said cutters simultaneously to machine the several areas in opposition therewith.

12. The combination of claim 11 in which one of the arms is not displaceable but another of the arms may be temporarily displaced to accommodate replacements of the idle position into its ,efiective posi- 13. The combination of claim 11 in which the work-support is spring-supported and in which a plunger is arranged to press directly against the work and, by actlng through it, to depress both the work and the work-support.

14. A back-facing apparatus combinlng a depressiblework-support; a non-depressible support for a facing-tool; a tubular facing tool journaled in said support; a depressible head; a spring-pressed power-rotated stub yieldably mounted in said head in coaxial alignment with said facing-tool and adapted during the descent of said head to enter the bore of said facing-tool in splined relation therewith to rotate it; and a plunger op erative after the establishment of said splined relation to depress the work and through it the Work-support and thereby cause the work to move into contact with said facing-tool until the back-facing operation has been completed.

15.. In a back-facing machine, two relatively shiftable supports; a tubular facingtool journaled in the one; a power-rotated stub yieldably journaled in the other in 00- axial alignment Withsaid facing-tool; a

work-support for mounting work with its perforation in alignment with said stub; and means for producing relative approachments between said supports first to en gage said facing-tool and stub in propelling relation and then to eflect an engagement between the then-rotating facing-tool and the work to accomplish the back-facing operation.

16. A back-facing apparatuscombinin a depressible work-support; a non-depressi le support for a facing-tool; a tubular facingtool journaled in said support; a-depres'sible head; a power-rotated .stub yieldably mounted in said head in-coaxial alignment with said facing-tool and adapted during the descent of said head impositively to enter the bore-of said facing-tool in splined relation therewith to rotate it; and means operative after the establishment of said 1 splined relation to depress the work-support and thereby cause the work to move into contact with said facing-tool until the backfacing operation has been completed.

17. A back-facing apparatus combining a depres'sible work-support; a tool-support adapted to be shifted laterally from an idle position into an operative relation with the work; a tubular facing-tool journaled' in said support; a head; a power-rotated stub yieldably mounted in sald head in coaxial alignment with said facing-tool and ada ted'to be impositively depressed to enter t e bore of said facing-tool in splined engagement therewith; and means operative after the establishment of said splined engagement to depress the work-support and thereby cause the work bodily to move into contact with said facing-tool until the back-facing operation has been com letd.

18 An apparatus or simultaneously machinmg several indirectly accessible areas,

of work, said apparatus 'combini a plurality of arms eac shaped indepeii ently to terminate adjacent a respective area; a plurality of isolated cutters, each independently journaled on the extremities of said arms respectively; a plurality of positively rotated driving shafts adapted to be projected along paths unobstructed by the work to establish propelling relations with the respective cutters; a work-support; and-means for producing a relative approachment between said work-support and said arms to cause said cutters simultaneously to machine the several areas in opposition therewith.

19. A back-facing apparatus combining a depressible work-support; a non-depressible support for a facing-tool; a tubular facing tool journaled in said support; a depressible head; a spring-pressed power-rotated stub yieldably mounted in said head in coaxial alignment with said facing-tool and adapted during the descent of said head impositively to enter the bore of said facingtool in splined relation therewith to rotate it; and a plunger operative after the establishment of said splined relation to depress the work and through it the work-support and thereby cause the work to move into contact with said facing-tool until the backfacing operation has been completed.

20. In combination with a machine tool equipped with arotatable and translatable spindle and a work-support; a back-facing attachment comprising a fixture adapted to be secured to the work-support; a worksupporting plate yieldingly embodied in said fixture; a rotatably ournaled back-facing tool rigidly supported in situ behind a surface of the work to be machined and in alignment with an orifice therein; a stub rotatably and translatably carried by the spindle and adapted upon translation of said spindle to project through the orifice j in the work and to establish a driving connection with the facing tool; and means to move the work bodily into engagement with the tool to effect the facing operation.

21. In combination with a machine-tool equipped with a rotatin spindle, a worksupport and means to e ect relative movement between the spindle and the work-support; aback-facing attachment comprising a fixture adapted to be held upon said worksupport; an auxiliary work-support yieldingly carried by said fixture; a rotatably journaled socketed baclefacing tool supported by said fixture and located adjacent the surface to be faced and in alignment with orted upon said an orifice in the work sup d b d carrle y sa1 auxiliary support; a stu spindle and adapted to be inserted through the orifice in the work and into the socket in the facing tool; and a pressure member nontranslatable relative to the spindle and socketed cutting tool rotatably journaled beneath a portion of the work and in alignment with an aperture therein; a stub carried by said spindle and adapted to be projected into the socket in the cutting-tool; and a pressure member carried by said toolhead adapted to be brought into contact with the work to depress it ito engagement with the cutting-tool to effect a back-facing operat1on.

23. An apparatus for tooling an indirectly approachable region of work combining a work-support; an adjustably mounted arm shaped to reach said region; means permitting said arm to be moved from an inoperative position to an operative position; an iso lated tool journaled on said arm; means to lock said arm in its operative position with its tool in opposition to the region to be machined; a normally disconnected driver adapted to be projected through an aperture in the work and into propelling engagement with said tool; and means for then effecting relative movement between the arm and the work-support to engage the tool with the work and cause it to eration onsaid region.

In witness whereof, I have hereunto subscribed my name.

FREBERT J. PETERS;

perform its tooling op- 

